Home Forums Gear Hunting Trucks and Four-Wheel Drives Should I switch to synthetic at 260,000 miles?

I switched to synthetic in my F150 and my wife's 4-runner last year, with no issues.

I recently picked up a '97 4-runner that will need an oil change soon. Will I be asking for trouble to switch over to Mobil 1 high mileage? I have some on the shelf that I use for my other vehicles, but the internet is full of opinions- both ways.

What say you?

I switched with a Chevy pickup with 160k. It was using about a qt of oil in 1000 miles before and the Mobile 1 cut that in half.

I've never run anything that high mileage, but I'd switch.

Everything I've read said it will clean the engine up and possibly allow it to start leaking some. Give it a try and see how it goes. I've been hearing alot about how these older 4 runners last forever. May have to try one

I wouldn't change what ever got it to 260000. My Ford Explorer just went over 200000. Everytime I take it in for an oil change they try to talk me into something new for it. I tell'm it ain't gonna happen

Today is my last day with the Explorer which has now attained "hooptie" status. The drivetrain is still 100% but the electronics are are going haywire. By the end of the day today I'll be in a Jeep Wrangler. Wahooo!

Reminds me of the story of my great grandma who used well water at her house. The neighbor down the road was over for coffee break one afternoon, and asked if she minded if he tested her water (he was on the rural water board, city-water if you will). She said sure, he went out to the truck, got the little test kit that tested for who knows what contaminants. Ran the test and said "Grace, this well water is going to kill you.". I'm thinking she was in her 80's at the time, lived to be 102, said "well, its taking its own sweet time".

There are lots of myths about synthetic oil. I have become a fan for use in Ford diesels. It doesn't wear out, only gets dirty. It is very helpful for starting in cold weather. I would not be afraid to try it in a high mileage engine.

BITOG.com : lubrication heaven

No,but the additives are depleted which for all intents and purposes means the oil is "worn" out.

You're playing with fire if you think otherwise.

Mossy,
With secondary filtration, some oil has gone a million miles in the same engine. It is possible to periodically replentish additives at around every 25-40,000 miles.

Okay, since you brought it up, WHOSE secondary/bypass filtration? I've recently been made aware of this and I'm keenly interested.

Exactly. Most guys running a bypass filter are having (should be anyways) the oil analyzed at 25-30K miles. Then you're replenishing the additives when you top off the oil level.

My point was, that its not as simple as saying oil doesn't wear out.

+1

I grew up working in my uncles garage, he had a rule you start with a good oil and don't switch once you break it in. 50 years later and I am on my 5th or 6th car that has pasted 200k. Currently my Dakota is is at 260k miles and still doesn't burn oil, my local lube shop wants to change me over to high mileage oil. No way will I switch a clean running engine.

When my brother died a few years ago, I inherited his '87 Bronco II with 235k. I had no idea what oil he'd been using so I went with Mobile 1. So far it's worked fine. It didn't use any oil when I got it and it doesn't use any now at 245k. It's my daily driver.

I ended up making the switch 2500 miles ago and...............nothing happened. At 263,400 miles, the old 97 4-runner has not only been leak free, but I have yet to add a drop of oil.

I started using M1 when I was doing a lot of cross country trips. While I never switched a vehicle with 260,000 miles I have switched a few over 100,000 and the motors were about the only good things left when I finally sent the vehicles down the road. Some with over 200K.

But you've already got 260K, whatever you're doing is working. I don't think switching will hurt, but not sure it will do much but add a few more miles between changes at this point.

Yep. I want to extend mileage between changes.

I switched to synthetic at 100K on my 97 Tahoe and it started leaking at the rear main. I switched back to regular oil and go 5K between changes.

I run synthetic lubes in my 01 Dodge Cummins, but regular oil in the engine. Top shelf stuff, Delo, Rotella or Valvoline Blue and a Baldwin filter.

I agree that a good oil and filter is all you need. See www.bobistheoilguy.com for a unique look at oil and grease perspectives.

I bought an '08 Dodge Cummins last summer. After the dealers oil change ran out, I put in M1 Turbo Diesel. We have a local farm store chain here that beat Wally's price by $4/gal (D&B Supply if any of you are in SW Idaho and want to know).

Been running Rotella in my 2005 Dodge/Cummins and using Baldwin or Amsoil filters changing at 5000 miles. Just turned 165K . I am due for another drive line lube change.